I'll grant that. As long as a belief in God isn't taken to
extremes. And certainly belief that a medicine will work even if there is no active ingredient in the "medicine" can have
benefits.
However Will Ross does have a point; unquestioning belief in unfounded claims can be entirely impractical. Unfounded claims include those which are supposedly backed up but haven't been verified by you (i.e., a reference to a scientific journal is useless if that journal doesn't exist. Verify references). And that's what it comes down to for me, being able to verify that extraordinary claims are valid.
Some extraordinary claims can be easily tested by an individual. E.g., 30-day trials of proposals where all the information needed is freely available. But some can't be tested without shelling out a significant amount of cash. Situations like that is where there is danger of being ripped off.